MariaDB 10.6

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create table f16 as
    select cast('2021-07-05 06:00:10' as datetime) as dateEvent, 2.0 as value union all
    select cast('2021-07-05 14:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-05 20:00:10' as datetime) as dateEvent, 4.0 as value union all
    select cast('2021-07-06 06:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-06 14:00:10' as datetime) as dateEvent, 1.0 as value union all
    select cast('2021-07-06 20:00:10' as datetime) as dateEvent, 5.0 as value union all
    select cast('2021-07-07 06:00:10' as datetime) as dateEvent, 4.0 as value union all
    select cast('2021-07-07 14:00:10' as datetime) as dateEvent, 2.0 as value union all
    select cast('2021-07-07 20:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-08 06:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-08 14:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-08 20:00:10' as datetime) as dateEvent, 6.0 as value union all
    select cast('2021-07-09 06:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-09 14:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-09 20:00:10' as datetime) as dateEvent, 5.0 as value union all
    select cast('2021-07-10 06:00:10' as datetime) as dateEvent, 2.0 as value union all
    select cast('2021-07-10 14:00:10' as datetime) as dateEvent, 3.0 as value union all
    select cast('2021-07-10 20:00:10' as datetime) as dateEvent, 1.0 as value

dateEvent	value	avg_10
2021-07-05 06:00:10	2.0	2.00000
2021-07-05 14:00:10	3.0	2.50000
2021-07-05 20:00:10	4.0	3.00000
2021-07-06 06:00:10	3.0	3.00000
2021-07-06 14:00:10	1.0	2.60000
2021-07-06 20:00:10	5.0	3.00000
2021-07-07 06:00:10	4.0	3.14286
2021-07-07 14:00:10	2.0	3.00000
2021-07-07 20:00:10	3.0	3.00000
2021-07-08 06:00:10	3.0	3.00000
2021-07-08 14:00:10	3.0	3.00000
2021-07-08 20:00:10	6.0	3.36364
2021-07-09 06:00:10	3.0	3.36364
2021-07-09 14:00:10	3.0	3.27273
2021-07-09 20:00:10	5.0	3.45455
2021-07-10 06:00:10	2.0	3.54545
2021-07-10 14:00:10	3.0	3.36364
2021-07-10 20:00:10	1.0	3.09091